iOS导航栏随滑动渐隐渐现且不影响push页面导航栏的实现方式

// 自定义导航栏视图

@property ( nonatomic , strong ) UIView * naviView;

viewDidLoad中:

if ([ self respondsToSelector : @selector (setEdgesForExtendedLayout:)])
    {
        [ self setEdgesForExtendedLayout : UIRectEdgeNone ];

    }

self . naviView = [[ UIView alloc ] initWithFrame : CGRectMake ( 0 , 0 , YJScreenWidth , 64 )];
    self . naviView . backgroundColor = THEME_Color ;
    [ self . view addSubview : self . naviView ];

    [self.view bringSubviewToFront:self.naviView];

- ( void )viewWillAppear:( BOOL )animated
{
    [ super viewWillAppear :animated];
    [ self . navigationController setNavigationBarHidden : YES animated :animated];
}

- ( void )viewWillDisappear:( BOOL )animated
{
    [ super viewWillDisappear :animated];
    [ self . navigationController setNavigationBarHidden : NO animated :animated];

}

#pragma mark - scrollViewDelegate
- ( void )scrollViewDidScroll:( UIScrollView *)scrollView
{
    CGFloat alpha = scrollView. contentOffset . y / 100 ;
    if (alpha >= 1 ) {
        alpha = 1 ;
    } else if (alpha <= 0 )
    {
        alpha = 0 ;
    }
    self . naviView . backgroundColor = [ THEME_Color colorWithAlphaComponent :alpha];

}